On Fri, 15 Jul 2011, Sakari Ailus wrote: > Hi Guennadi, > > Thanks for the comments. > > On Thu, Jul 14, 2011 at 07:56:10PM +0200, Guennadi Liakhovetski wrote: > > On Thu, 14 Jul 2011, Sakari Ailus wrote: > > > > > Hi all, > > > > > > I was thinking about the sensor binning controls. > > > > What wrong with just doing S_FMT on the subdev pad? Binning does in fact > > implement scaling. > > Nothing really. Supporting setting binning using S_FMT is fine. > > However, the interface does not express binning capabilities in any way. To > effectively use binning settings one must know the capabilities. Binning is > scaling but the choices are so coarse that the capabilities are a must. > > The capabilities could be found implicitly by trying out different formats > and looking back at the result. That's still not quite trivial. > > If there would be a good way to enumerate the binning capabilities, combined > with S_FMT it'd be close to perfect. Then how about something like ENUM_SCALE(S)? Thanks Guennadi > > > > I have a sensor which can do binning both horizontally and vertically, but > > > the two are connected. So, the sensor supports e.g. 3x1 and 1x3 binning but > > > not 3x3. > > > > > > However, most (I assume) sensors do not have dependencies between the two. > > > The interface which would be provided to the user still should be able to > > > tell what is supported, whether the two are independent or not. > > > > > > I have a few ideas how to achieve this. > > > > > > 1. Implement dependent binning as a menu control. The user will have an easy > > > way to enumerate binning and select it. If horizontal and vertical binning > > > factors are independent, two integer controls are provided. The downside is > > > that there are two ways to do this, and integer to string and back > > > conversions involved. > > > > > > 2. Menu control is used all the time. The benefit is that the user gets a > > > single interface, but the downside is that if there are many possible > > > binning factors both horizontally and vertically, the size of the menu grows > > > large. Typically binning ends at 2 or 4, though. > > > > > > 3. Implement two integer controls. The user is responsible for selecting a > > > valid configuration. A way to enumerate possible values would have to be > > > implemented. One option would be an ioctl but I don't like the idea. > > > > > > Comments are welcome as always. > > > > > > Cheers, > > > > > > -- > > > Sakari Ailus > > > sakari.ailus@xxxxxx > > > -- > > > To unsubscribe from this list: send the line "unsubscribe linux-media" in > > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > > > > > --- > > Guennadi Liakhovetski, Ph.D. > > Freelance Open-Source Software Developer > > http://www.open-technology.de/ > > -- > Sakari Ailus > sakari.ailus@xxxxxx > --- Guennadi Liakhovetski, Ph.D. Freelance Open-Source Software Developer http://www.open-technology.de/ -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
